I've also never used the adb remount, but as for your comment about pushing... push isn't ran from "adb shell"
you should be doing "adb push <file to push> /path/to/where/it/goes/<file>"
Of course this needs root and, in places where the NAND is mounted as read only, you must do the remount option with r/w
There are tons of guides on how to do this on our forum, but I'm too lazy to find them.
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